I've had my iGPSPORT i50S for a few months now and am generally impressed. It's a fairly basic GPS/Beidou computer that can interface to a heart rate monitor, cadence sensor, and wheel speed sensor, but not a power monitor. The screen is a simple LCD display with no maps or navigation. I ordered a package that included the heart rate, cadence, and wheel speed sensors as well as a mount.
The good:
- Garmin-style mounts are cheap and easy to find.
- Speed, distance, and elevation calculations are all fairly close to what I've calculated with other means.
- It was easy to pair the device with the sensors, and the connectivity has generally been good.
- Battery life seems pretty good. It could easily last an entire day of riding.
- It's durable. I left it on the roof of my car and it fell off when I went around a corner. I found it a couple days later, lying in the gutter. There's just a minor scratch or two.
- iGPSPORT has good tech support. I've emailed them twice with questions and got useful answers within 24 hours in both cases.
The not as good:
- It seems to lose GPS reception easily when riding in forested areas. I've had a couple rides where the reception drops out and recovers a few seconds later, and it happens repeatedly. The beep when this happens gets annoying, although the total distance still seemed accurate. (I did not have the wheel speed sensor on the bike at this time. There aren't many trees where I usually ride, so this isn't a big issue for me.)
- When I first got it, it reset itself periodically during a ride. I emailed iGPSPORT and they suggested a software update, which fixed the issue.
- The app is a bit unpolished. Some of the screens are awkward to use, and there are some issues working in miles.
- The "odometer" on the computer is not adjustable, and there is no support for multiple bikes on the computer itself. However, you can download the recorded rids with the app and then assign them to different bikes. The app will then show the cumulative distance for each bike.
Overall, I'd happily buy it again. The wheel speed sensor isn't essential, but it does allow it to detect motion and start recording more quickly than when on GPS alone. It should also help when there are satellite reception issues.